Download implementation of embedded bluetooth data

IJRET: International Journal of Research in Engineering and Technology
ISSN: 2319-1163
Fig-1.EBIBS architecture
2.2 Device Hardware Framework
The EBIBS is based on ARM hardware development platform
and uses Samsung S3C2440 as core processor. The microprocessor constitutes core embedded system with 64MB
SDRAM and 64M Flash. It runs ARM-Linux-2.6.12core
operation system, where Bluetooth bus-system is configured to
provide driver for USE Bluetooth adapter. As core
communication component, Bluetooth adapter connects to USB
device interface. LED and key constitute hardware part of user
interaction interface. The system is easy to extend function and
migration system. Developers can download operation system
core and upper applications to SDRAM or Flash via USB Host
interface and debug applications with RS-232 serial port.
Fig-2. Device software framework
Information broadcast module and information update module
are designed according to official Bluetooth protocol BlueZ and
OBEX, where BlueZ includes two parts of core library bluezlibs and bluez-utils utility. The latter provide developers with
tools support for upper-level applications.OBEX protocol is
realized by OpenOBEX application function library. Therefore,
the design firstly implements migration from BlueZ and
OpenOBEX to ARM9 hardware platform system and then
achieves other functions. LED and key driver are designed
according to embedded character-driven technology.
3. DATA BROADCAST IMPLEMENT
2.3 Device. Software Framework
Software framework can be divided into two main modules,
namely information broadcast module and information update
module. The information broadcast module can be further
divided into three sub-modules: information management
module, device query module and information transform
module. Information management module is responsible for
sorting information so that user can send it in specific order. The
device query module uses Service Discovery Protocol (SDP) to
obtain information of surrounding Bluetooth devices service and
automatically filter remote device with object push service as
discovery objects. As core module, information transform
module complete information broadcasting. LED driver and key
driver are added into system to provide low level software
support for user interaction functions. The software framework
of EBIBS is shown in Fig. 2.
3.3 Unicast Implement
As information unicast basis of information broadcast, it is also
the core of design. The system firstly complete file transmission
process in single point mode. The process is based on OBEX
protocol and uses OPENOBEX function library achieves object
push on some remote device. OPENOBEX function library
completes session layer operation and corresponding object
model description of OBEX protocol. Fig. 3 shows complete
process of object push.
(1) OBEX-INIT() function is used to initiate OBEX
entity,including initiate transform type, socket description,
maximum size of send packet and maximum size of receive
packet and then return a entity handle.
(2)Store target Bluetooth device address, object push service
channel number and information file name to corresponding
local variables.
(3)Call BtOBEX_TransportConnect() function establish
transmission connection. The function firstly initiate
transmission attributes of local and remote OBEX entities and
then call socket () system function to create local socket. The
bind () function is used to bind socket and process and connect()
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Volume: 01 Issue: 03 | Nov-2012, Available @ http://www.ijret.org
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